Adaptive immune features of natural killer cells

Nature. 2009 Jan 29;457(7229):557-61. doi: 10.1038/nature07665. Epub 2009 Jan 11.

Abstract

In an adaptive immune response, naive T cells proliferate during infection and generate long-lived memory cells that undergo secondary expansion after a repeat encounter with the same pathogen. Although natural killer (NK) cells have traditionally been classified as cells of the innate immune system, they share many similarities with cytotoxic T lymphocytes. We use a mouse model of cytomegalovirus infection to show that, like T cells, NK cells bearing the virus-specific Ly49H receptor proliferate 100-fold in the spleen and 1,000-fold in the liver after infection. After a contraction phase, Ly49H-positive NK cells reside in lymphoid and non-lymphoid organs for several months. These self-renewing 'memory' NK cells rapidly degranulate and produce cytokines on reactivation. Adoptive transfer of these NK cells into naive animals followed by viral challenge results in a robust secondary expansion and protective immunity. These findings reveal properties of NK cells that were previously attributed only to cells of the adaptive immune system.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / deficiency
  • Adaptor Proteins, Signal Transducing / genetics
  • Adoptive Transfer
  • Animals
  • Cell Proliferation
  • Immunologic Memory / immunology*
  • Killer Cells, Natural / cytology*
  • Killer Cells, Natural / immunology*
  • Lymphoid Tissue / immunology
  • Mice
  • Mice, Congenic
  • Mice, Inbred C57BL
  • Models, Immunological*
  • Muromegalovirus / immunology
  • Muromegalovirus / physiology
  • Phenotype
  • T-Lymphocytes, Cytotoxic / immunology

Substances

  • Adaptor Proteins, Signal Transducing
  • Tyrobp protein, mouse